Human Phys 4.6 Flashcards
Flow mediated dilation
Shear stress increases eNOS stimulation which leads to nitric oxide release from endothelial cells to smooth cells
Once in smooth cells cGMP increases and causes relaxation and vasodilation
How does blood flow in the arteries during diastole to compliance reserves?
Recoil of arteries
Hydrostatic capillary pressure use the main starling force that drives what?
Fluid filtration
What is the key compound in the FMD used to signal dilation in arteries?
eNOS
Functional sympatholysis plays what role in metabolic regulation of blood flow?
Decreases metabolite activity stimulating the SNS, but overridden by vasodilation pathways
In what chronic disease is functional sympatholysis impaired?
Hypertension
How does blood flow in arteries during diastole?
Due to elastic reserves
Why does the venous side get an IV?
Because a change in volume does not effect pressure very much
Myogenic autoregulation
Sudden stretch of small blood vessels stimulates vascular smooth muscle cells contraction via stretched induced depolarization
What happens in myogenic autoregulation when flow increases?
Pressure increases too leading to increased VSMC contraction which increases resistance and decreases flow back to normal
What does metabolic autoregulation override?
Myogenic autoregulation
What is myogenic autoregulation governed by?
VSMC
What does increase wall stress lead to?
Increase VSMC contraction
What does contraction of VSMC cause?
Decrease radius and restores wall stress
What is flow mediated dilation governed by?
Endothelial cell
